JP2011038715A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a refrigerator capable of improving energy-saving properties and preservability of foods. <P>SOLUTION: Cold air is supplied to a refrigeration temperature zone chamber by operating a blower, in a state with a compressor stopped, a refrigeration chamber damper open, and a freezing chamber damper closed. When it is determined that there is less frost formation by comparing a temperature gradient of a cooler with a set value, the blower is stopped, the refrigeration chamber damper is closed, and a defrosting heater is operated, after the cooler reaches a prescribed temperature. When it is determined that there is much frosting by comparing the temperature gradient of the cooler with the set value, the defrosting heater is operated; and then, the blower is stopped and the refrigeration chamber damper is closed, after the cooler reaches the prescribed temperature. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a refrigerator.

  Due to evaporation of moisture from food stored in the refrigerator and intrusion of outside air when the door is opened and closed, moisture condenses in the minus temperature cooler and grows as frost. When frost grows on the fin surface of the cooler, the ventilation resistance gradually increases, so that heat cannot be sufficiently exchanged, resulting in a decrease in cooling performance. Therefore, it is not easy to improve the air side heat exchange performance by narrowing the fin pitch of the cooler. However, there is a great need for a refrigerator that achieves both improved energy saving and a large capacity of the refrigerator, and it is important to develop a high-performance cooling unit that takes into account the defrosting operation.

  A conventional defrosting method for a cooler uses a defrosting heater (for example, a glass tube heater) provided on the lower side of the cooler and heats it until a temperature sensor installed in the cooler reaches a predetermined temperature. The frost is thawed. Since this system heats not only the cooler but also the entire cooler installation space with a heater for defrosting, it is characterized in that there is little unmelted frost. However, since the heating energy is input in addition to the purpose of defrosting the frost that has grown on the cooler, the defrosting method is wasteful from the viewpoint of energy saving. Except for the purpose of defrosting, all the energy input into the chamber becomes a heat load, which causes the temperature in the chamber to rise, and eventually the heating input by the cooling operation (cooling recovery operation) after defrosting is completed. It is necessary to remove energy. Therefore, in order to improve energy saving, it is important to reduce the input energy from the outside at the time of defrosting.

  Many manufacturers have adopted defrosting using a defrosting heater, and many methods for reducing defrosting time for the purpose of energy saving have been disclosed. In other words, when the amount of frost formation is small, the amount of frost formation other than the cooler is small, so it is expected that the frequency of frost unresolved is low. The defrosting is finished early. For example, the following means are disclosed regarding the method of predicting the amount of frost formation during operation of the refrigerator. The number of times the door is opened and closed, the compressor operating time, the outside temperature, etc. are general measurement items used for estimating the amount of frost formation, and there are examples that have already been applied to products. In JP-A-8-261629, the amount of frost formation is predicted according to the number of doors opened and closed. When the amount of frost formation is smaller than the reference value of the number of doors opened and closed, it is determined that the amount of frost formation is small, and defrosting is performed more than usual. The end temperature is lowered to shorten the defrosting time to reduce power consumption. In JP-A-8-94234, in order to optimize the defrost cycle, the amount of frost formation is estimated from the temperature gradient by measuring the temperature of the cooler during defrosting. When the amount of frost formation is large, it takes time from the start of defrosting until the frost starts to melt, so the temperature gradient becomes gentle. Conversely, when the amount of frost formation is small, the temperature gradient becomes steep. Therefore, since the amount of frost formation is large when the temperature gradient of the cooler during defrosting is gentle, the defrosting interval is optimized by making it shorter than the defrosting interval currently performed.

JP-A-8-261629 JP-A-8-94234

  However, in the method of defrosting by heating from the lower part of the cooler using a defrost heater, the heat transfer between the defrost heater and the frost is due to natural convection using air as a medium, and it is difficult to shorten the defrost time. . There is also a method in which a defrost heater is directly attached to the pipe of the cooler to improve the heat transfer performance from the heater, but this is a fundamental solution to shortening the defrost time and reducing the input energy during defrosting. Absent.

  From a different perspective, the frost that has grown on the cooler can be thought of as having accumulated cold energy. The conventional method is solved by applying thermal energy to the frost from the outside by a defrost heater. Therefore, utilization of the cold energy stored in the frost is not considered.

  Considering only the improvement in energy saving performance, only the internal fan is operated, and only the heat load entering the internal storage from outside the storage, that is, without using the defrosting heater, the cooler frost is only generated by the internal fan. The best method is to vent the cold air generated at that time to the refrigerator compartment or vegetable compartment. However, in a refrigerator having a plurality of temperature zones, that is, a refrigerator having both a refrigeration temperature zone and a refrigeration temperature zone, it is possible to cool the refrigeration temperature zone by the frost heat energy during the defrosting operation. Since the cold air temperature is higher than the freezing temperature zone, the freezing room cannot be cooled. Therefore, in such a defrosting operation, since the cooling air blowing to the freezer compartment is stopped, the defrosting operation time must be shortened for the purpose of temperature control of the freezer compartment, and the preservation of frozen food must be maintained. Don't be.

  The amount of frost formation on the cooler can be determined by the length of time during which the frost undergoes a phase change (a change in which frost is melted and turns into water. The temperature of the cooler during the phase change is approximately 0 ° C.). If the amount of frost formation is small, the phase change time is short, and if the amount of frost formation is large, the phase change time is long. However, when determining the amount of frost formation based on the phase change time, most of the defrosting time has already elapsed when the determination is made, and it is determined that the amount of frost formation is large at this time, and means for shortening the defrosting time Even if it is taken, it may be too late. In the prior art, there is no means for shortening the defrosting time during the defrosting. Under such circumstances, the temperature of the freezer compartment rises, causing problems when storing frozen food.

  Further, the conventional defrosting timing often uses the number of times the door is opened and closed in a certain time, the cumulative operation time of the compressor, the outside temperature, and the like. However, for example, when the operating time of the refrigerator compartment (including the vegetable compartment) is long, or when a large amount of food is put in the refrigerator compartment, the amount of moisture brought into the refrigerator from the outside is large, resulting in frost formation. The amount is large, and the defrosting timing by the conventional method is not always sufficient. When the above operation is performed, it may be determined that the amount of frost formation is small by the conventional method, and the amount of frost formation may actually increase. Therefore, even in such a case, it is necessary to provide means for shortening the defrosting time during the defrosting.

  The present invention has been made to solve the above problems, and an object of the present invention is to obtain a refrigerator having improved energy saving and food storage stability.

  In order to solve the above problems, the present invention provides a refrigeration temperature zone chamber and a freezing temperature zone chamber provided in a refrigerator main body, a compressor provided in the refrigerator main body for compressing refrigerant, and a rear of the freezing temperature zone chamber. A cooler chamber in which a cooler is disposed, a blower that supplies cool air from the cooler chamber to the refrigeration temperature zone chamber and the refrigeration temperature zone chamber, and an amount of cool air supplied to the refrigeration temperature zone chamber A refrigerating room damper that controls the amount of cold air supplied to the freezing temperature zone chamber, a defrost heater that is provided in the cooler chamber and defrosts the cooler, and stops the compressor, The refrigerator is operated with the refrigerator compartment damper opened and the freezer compartment damper closed to supply cool air to the refrigerator compartment, and the temperature gradient of the cooler is compared with the set value to reduce frost formation. When it is determined that the cooler has reached a predetermined temperature When the blower is stopped and the refrigerator compartment damper is closed and the defrost heater is operated, the temperature gradient of the cooler is compared with a set value, and it is determined that there is much frost formation, the defrost heater is operated. The blower is stopped and the refrigerator compartment damper is closed after the cooler reaches a predetermined temperature.

  Moreover, according to the amount of frost formation of the said cooler, at least any one of the electricity supply rate of the said defrost heater or the rotation speed of the said air blower is controlled.

  In addition, a door sensor for detecting opening and closing of the door of the freezing temperature zone chamber is provided, and at least one of the energization rate of the defrost heater or the rotation speed of the blower is controlled according to a detection value of the door sensor. Features.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerator which improved energy saving property and the preservability of foodstuffs can be obtained.

It is a front view of the refrigerator which concerns on embodiment of this invention. It is side surface sectional drawing of a refrigerator. The cooler is viewed from the front of the refrigerator. It is sectional drawing which looked at the cooler from the side of the refrigerator. It is an example of the normal cooling operation pattern of the refrigerator which concerns on embodiment of this invention. It is an example of the defrost operation pattern of the refrigerator which concerns on embodiment of this invention. It is a flowchart regarding determination of the amount of frost formation at the time of defrosting of this invention. It is a control flow figure in case there exists freezer compartment door opening and closing during a defrost operation. It is a control flow figure in case there exists freezer compartment door opening and closing during a defrost operation. It is a control flow figure in case there exists freezer compartment door opening and closing during a defrost operation. It is an example of the result at the time of performing defrost operation when there is little frost formation amount. It is an example of the result at the time of defrosting operation when there is much frost formation amount.

  FIG. 1 is a front view of a refrigerator according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view in the side direction of the refrigerator. The refrigerator 8 according to the present embodiment includes a refrigerator room 9, an ice making room 30, an upper freezing room 10 (next to the ice making room 30), a lower freezing room 11, and a vegetable room 12 from above. The refrigerating room 9 is provided with front-opening refrigerating room doors 9a and 9b divided into left and right sides. The ice making room 30, the upper freezing room 10, the lower freezing room 11, and the vegetable room 12 are each a drawer type ice making room door 10a. , An upper freezer compartment door 10b, a lower freezer compartment door 11a, and a vegetable compartment door 12a. The refrigerator 8 includes a door sensor (not shown) that detects the open / closed state of each of the doors 9a, 9b, 10a, 10b, 11a, and 12a, an alarm that notifies the user of the door open state (not shown), and the refrigerator compartment 9 Temperature setting means (not shown), and temperature setting means (not shown) for the upper freezer compartment 10 and the lower freezer compartment 11 are connected to the control unit of the refrigerator. In order to cool the inside of the refrigerator, a refrigerator 8 is incorporated in the refrigerator 8, and a compressor 1, a condenser (not shown), a throttle (not shown), and a cooler 4 are configured. Connected sequentially.

  As shown in FIG. 2, the outside of the refrigerator 8 and the inside of the refrigerator are separated by a heat insulating box 31. In the refrigerator, the refrigerator compartment 9 is separated from the upper freezer compartment 10 and the ice making chamber 30 by the heat insulating partition wall 32, and the lower freezer compartment 11 and the vegetable compartment 12 are separated by the heat insulating partition wall 33. The cooler 4 is provided in a cooler chamber 34 provided substantially at the back of the lower freezing chamber 11, and the return air exchanges heat with the cooler 4 by an internal fan 5 provided above the cooler 4. Then, the cooled air is blown into each chamber. In the case of the refrigerating room cooling operation (hereinafter referred to as “R operation”) for supplying cold air to the refrigerating room 9 and the vegetable room 12, the refrigerating room damper 6 (hereinafter referred to as “R damper”) is opened (at this time, the freezing room damper). 13 (hereinafter referred to as “F damper”) is closed) to supply cold air. The air that has cooled the refrigerator compartment 9 is sent to the vegetable compartment 12 via a duct 24 (see FIG. 3) connected to the vegetable compartment 12. The cold air sent to the vegetable compartment 12 passes through the vegetable compartment return air passage 17 and the vegetable compartment cold air return port 21 provided in the heat insulating partition wall 33 and is returned to the cooler 4. In the case of a freezer cooling operation (hereinafter referred to as “F operation”) in which cold air is supplied to the upper freezer chamber 10 and the lower freezer chamber 11, the freezer air is passed through the freezer air passage 15 by opening the freezer damper 13. Supply. The cold air supplied to the upper freezer compartment 10 and the lower freezer compartment 11 is returned to the cooler 4 from the freezer compartment cold air return port 14. R operation, F operation, or cooling operation (refrigeration room + freezing room) for cooling everything in the warehouse (hereinafter referred to as “FR operation”. Both R damper 6 and F damper 13 are open) Each operation is automatically determined by comparing the temperature with an internal temperature sensor provided in the internal space, and a cooling operation is performed. A defrost heater 18 is provided at the lower part of the cooler 4 at the upper part of the internal tray 25, and the internal tray 25 discharges drain water generated during defrosting to the external tray 19 via the drain pipe 20. Can do. The drain water can be evaporated by the exhaust heat of the compressor 1 or the like.

  FIG. 3 shows the cooler 4 as viewed from the front of the refrigerator. FIG. 4 is a cross-sectional view of the cooler 4 as seen from the side of the refrigerator. A defrost heater 18 having a length substantially the same as the width of the cooler 4 is provided below the cooler 4. Further, a defrost sensor 26 for detecting the temperature of the cooler 4 is provided at the upper part of the cooler 4 (for example, the defrost sensor 26 is attached so as to contact the pipe of the cooler), and the defrost sensor The signal regarding the temperature detected by 26 is connected to the control part (not shown) of a refrigerator. The duct 24 connects the refrigerator compartment 9 and the vegetable compartment 12, and the cold air that has cooled the refrigerator compartment 9 is then supplied to the vegetable compartment 12 via the duct 24. Further, as shown in FIG. 4, the cold air supplied to the freezer compartments 10 and 11 is returned to the cooler 4 from the freezer compartment cold air return port 14. Further, the cold air supplied to the refrigerator compartment 9 and the vegetable compartment 12 is returned to the cooler 4 from the vegetable compartment cold air return port 21 via the vegetable compartment return air passage 17. The freezing compartment cold air return port 14 and the vegetable compartment cold air return port 21 have substantially the same opening length as the width direction of the cooler 4. In the case of F operation (cooling of the freezer compartment), after cooling the freezer compartment, the cold air is supplied from the freezer compartment cold air return port 14, and in the case of R operation (cooling the refrigerator compartment (including the vegetable compartment)), the refrigerator compartment and vegetables After cooling the chamber, the cool air is returned from the vegetable chamber cool air return port 21 to the cooling chamber 34 through the return port provided. In the case of FR operation (cooling of the entire room in the refrigerator), cold air is simultaneously returned to the cooler 4 from the freezer compartment cold air return port 14 and the vegetable compartment cold air return port 21. Accordingly, since the inflow pattern of the cool air into the cooler 4 varies greatly depending on the cooling operation pattern, the heat return performance of the cooler 4 and uniform frost formation are considered, and the cool air return ports 14 and 21 are almost the same as the width of the cooler. It is better to do.

  FIG. 5 is an example of a normal cooling operation pattern of the refrigerator according to the embodiment of the present invention. It consists of R operation (refrigeration operation), F operation (refrigeration operation), and operation using frost chill energy when the compressor is stopped, and the operation of the internal fan, R damper, F damper, and compressor in the cooling operation pattern It explains together. When the return air passes through the vicinity of the frost grown on the cooler 4, heat is exchanged, and the return cold air is cooled. The frost is initially at substantially the same temperature as the cooler 4, but the temperature of the frost rises due to heat exchange with the return air, and rises to almost 0 ° C. when the frost begins to melt. The section where the frost is melting is approximately 0 ° C. In the operation section using the cold energy of frost, the compressor 1 is stopped, the internal fan 5 is operated, the F damper 13 is closed, and the R damper 6 is opened. The internal fan 5 operates, for example, until the temperature detected by the defrost sensor 26 provided in the cooler 4 reaches about 3 ° C., and supplies cold air using cold energy of frost to the refrigerator compartment 9. After the frost utilization operation is completed, after the refrigerator compartment 9 is cooled, the compressor 1 is operated to start the R operation. At this time, the R damper 6 is open and the F damper 13 is closed. Since the refrigeration cycle for cooling the refrigeration temperature zone can be started with the temperature of the cooler 4 increased by starting the R operation after the frost utilization operation when the compressor is stopped, the operation is performed with high cycle efficiency. Is started. The R operation is switched to the F operation after reaching the set lower limit temperature of the refrigerator compartment 9. During the F operation, the R damper 6 is closed and the F damper 13 is opened. The rotational speed of the compressor 1 varies depending on the internal temperature and the external temperature at that time, but in the stable cooling operation, the R operation can lower the rotational speed of the compressor than the F operation. Become.

  FIG. 6 is an example of a defrosting operation pattern of the refrigerator according to the embodiment of the present invention. The defrosting operation of the present invention is different from the natural convection type defrosting method using the defrosting heater 18 which is a conventional method. That is, during the defrosting operation, the R damper 6 is opened, the F damper 13 is closed, the internal fan 5 is operated, and heat transfer is promoted by forced convection between the frost grown on the cooler 4 and the return air. The defrosting time is shortened, and the cold air generated at this time is sent to the refrigerator compartment 9 and the vegetable compartment 12 for cooling. Next, a specific method of the present defrosting method shown in FIG. 6 will be described. The operation pattern shown here is an example. Refrigerating room temperature, freezer room temperature, cooler temperature (temperature detected by the defrost sensor 26) and the status of the internal fan, R damper, F damper, compressor, and defrost heater are shown in time series. . The times for the cooler temperatures T0 to T4 are t0 to t4, respectively. At the start of the defrosting operation, for example, the freezing room is cooled immediately before the start of the defrosting in anticipation of an increase in the temperature of the freezing room during the defrosting. When the cooler temperature at the start of the defrosting operation is T0 (time t0) and the defrosting operation is automatically started, it can be considered that the cooler temperature T0 at the start is substantially constant. During defrosting, the R damper is open, the F damper is closed, the internal fan is operated, and the compressor is stopped. The cooler temperature rises due to heat exchange between the frost and the return air, and reaches the melting temperature T1 at time t1. The frost begins to melt from time t1, and the melting of frost is completed at time t2. During this time, since latent heat is released, the temperatures T1 and T2 are the same and are substantially constant at 0 ° C. The time from time t1 to t2 is proportional to the amount of frost formation of the cooler 4. That is, when the amount of frost formation is large, the time from time t1 to t2 becomes longer, and the time to reach the cooler temperature T0 to T1 also becomes longer. When the cooler temperature reaches T3 (for example, 3 ° C., time is t3), the operation of the internal fan is stopped, the R damper is closed, and the cooler is heated by the defrost heater. The defrost heater is continuously heated until the cooler temperature reaches T4 so that the cooler frost can be completely melted. T4 is an empirically determined temperature and is approximately 10 ° C. In the defrosting method shown in FIG. 6, only the internal fan is operated from the start of defrosting (cooler temperature T0) to the cooler temperature T3 to defrost, and at the same time, the cold air generated by the cooler is stored in the refrigerator room (including the vegetable room). ) And when the temperature reaches a predetermined temperature T3, the internal fan is stopped and heated by the defrost heater. At this time, the R damper should be closed.

  However, what should be noted here is that the above-described means is good for reducing the amount of power consumption during defrosting. For example, when the amount of frost formation is large, the interval between times t1 and t2 becomes long, During this time, the temperature of the freezer compartment may rise, which is a problem when storing frozen foods. Therefore, it is necessary to shorten the defrosting time by detecting the amount of frost formation and using the internal fan and the defrosting heater in combination. The defrosting heater during the defrosting operation shown in FIG. 6 can change an energization rate according to the amount of frost formation. The concept of the energization rate of the defrost heater during the defrosting operation will be described with reference to FIG.

  FIG. 7 is a method for determining the amount of frost formation during defrosting according to the present invention. The time t0 at the start of the defrosting operation and the cooler temperature T0 (detected by the defrost sensor 26) are stored in the storage device (S100). The cooler temperature T0 is often cooled in advance in anticipation of a temperature increase in the freezing room during defrosting, and the cooler temperature T0 is often substantially constant. Next, the R damper is opened and the F damper is closed, and cool air generated by the cooler is blown into the refrigerator compartment while operating the internal fan to defrost. At this time, the defrosting heater is OFF (S101). The determination of the amount of frost formation is performed as follows. The cooler temperature gradually increases from the start of defrosting, and reaches a temperature T1 (time t1) at which frost starts to melt. If the amount of frost formation is large, the time to reach the temperature T1 becomes long. Conversely, if the amount of frost formation is small, the time to reach the temperature T1 becomes short. Therefore, the determination of the amount of frost formation can be determined by the temperature gradient A from the defrost start temperature T0 to the temperature T1 (about 0 ° C.) at which the frost starts to melt. That is, temperature gradients A1 and A2 that are references for determining the amount of frost formation are obtained in advance. For example, when classifying the amount of frost formation into three ranges of large, medium and small, the following determination is made. When the temperature gradient A at the time of defrosting is larger than the temperature gradient A1, it determines with the amount of frost formation being small (S103). When the temperature gradient A at the time of defrosting is smaller than the temperature gradient A2, it determines with there being much frost formation (S105). Further, when the temperature gradient A is between A1 and A2, the amount of frost formation is determined to be intermediate (S104). When it is determined that the amount of frost formation is small (S103), only the internal fan is operated until the cooler temperature reaches T3. After the cooler temperature T3, the internal fan is turned off, the defrost heater is turned on, and the R fan is turned on. Close (S106). Thereafter, the defroster is heated until the cooler temperature reaches T4, and the defrosting is completed (S108).

  When it is determined that the amount of frost formation is intermediate (S104), the defrost heater is also turned on while the internal fan is operated to shorten the defrost time. The defrost heater can adjust the energization rate, for example, the energization rate is set to 50% (S109), and the process is continued until the cooler temperature reaches T3. After the cooler temperature T3, the internal fan is turned off, the defrost heater is turned on, and the R damper is closed (S106). Then, it is heated until the cooler temperature reaches T4 (S107), and the defrosting is finished (S108).

  When it is determined that the amount of frost formation is large (S105), the defrost heater is also turned on while the internal fan is operated to shorten the defrost time. In order to shorten the defrosting time because the amount of frost formation is large, the energization rate of the defrosting heater is set to 100% so as to shorten the time (S110), and the process is continued until the cooling temperature reaches T3. After the cooler temperature T3, the internal fan is turned off and only the defrost heater is heated (S106). Then, it heats until cooler temperature becomes T4, and complete | finishes defrosting (S108). It should be noted that the energization rate of the defrost heater can be adjusted in common S106 to S108 regardless of the amount of frost formation.

  8, FIG. 9 and FIG. 10 are control flow charts when the freezer compartment door is opened and closed during the defrosting operation. The defrosting operation is based on the control in which the energization rate of the defrosting heater is changed according to the amount of frost formation (see FIG. 7), but when the heat load in the refrigerator increases due to the opening and closing of the freezer door, It shifts to the method which complete | finishes a defrost time in the shortest irrespective of the amount of frost formation so that the preservability of frozen food may be maintained. That is, the mode which makes the electricity supply rate of a fan in a warehouse and a defrost heater 100% is provided. FIG. 8 shows that when the freezer compartment door is opened and closed after the start of defrosting and before determining the amount of frost formation (S111), the defrosting heater is turned on and the heater energization rate is set to 100% (S110). Change control to save time. The control method up to the end of defrosting is the same as in FIG. After judging that the amount of frost formation is small in FIG. 9, when the door of the freezer compartment is opened and closed (S111), the energization rate of the defrost heater is set to 100% (S110) so that the defrost time can be shortened. Change control. The control method up to the end of defrosting is the same as in FIG. FIG. 10 shows that when the freezing room door is opened and closed after determining that the amount of frost formation is intermediate (S111), the energization rate of the defrosting heater is set to 100% (S110), and the defrosting time can be shortened. To change.

  FIG. 11 and FIG. 12 are examples of the results when this defrosting operation is performed. Each of the frosting amount, the freezing room, and the cooling when the amount of frost formation is small (about 40 g) and when the amount of frost formation is large (about 230 g). It is an example of a time-dependent change of vessel temperature and electric power. Defrosting start (time t0, cooler temperature T0), frost melting start (time t1, cooler temperature T1), frost melting end (time t2, cooler temperature T2), internal fan stop (time t3, cooling) Temperature T3), defrosting is completed (time t4, cooler temperature T4). Since cold air is supplied to the refrigerator compartment from time t0 to t3, the refrigerator compartment temperature is cooled from about 10 ° C. to about 5 ° C. to 6 ° C. in any case. When the amount of frost formation is small (FIG. 11), the frost heating section (t0 to t1) is about 7 minutes, the frost melting section (t1 to t2) is about 8 minutes, the entire defrosting time is about 30 minutes, and the frost formation amount. When there are many (FIG. 12), a frost heating area (t0-t1) will be about 10 minutes, a frost melting area (t1-t2) will be about 13 minutes, and the whole defrost time will be about 40 minutes.

  As described above, a compressor that cools a cooler, a blower that circulates cold air cooled by the cooler to a freezer room, a refrigerator room, a vegetable room, and the like, and a refrigerator room that controls the amount of cold air supplied to the refrigerator room Refrigerator having a damper, a defrost heater for defrosting frost attached to the cooler, a freezer damper for controlling the amount of cool air supplied to the freezer, a partition plate for partitioning the freezer and cooler A cooler compartment duct is formed on the front side of the blower to send cold air to the refrigerator compartment damper side, a blower cover is provided between the partition plate and the cooler air duct to send cold air to the freezer compartment, and the cold air duct has a freezer In addition to sending cold air through the room damper, defrosting is performed during the cooling operation and defrosting of the refrigeration room, etc. due to the frost that has grown on the cooler, under the temperature monitoring by the temperature sensor in the refrigerator compartment and freezer compartment While being able to cool the refrigerator compartment etc. at the same time

  According to this, in the defrosting method that enables cooling operation of the refrigeration room and vegetable room by the cold energy of the frost grown on the cooler, and simultaneously achieves energy saving during defrosting and suppression of temperature rise in the freezer room, A refrigerator having means for detecting the amount of frost formation during defrosting can be realized.

  In addition, the temperature of the cooler and the operation time of the refrigerator are stored in a storage device as means for detecting the amount of frost during defrosting, and the temperature gradient from the start of defrosting of the cooler to the start of frost melting is used as a reference temperature gradient The amount of frost formation can be determined during the defrosting operation by comparing with, and a refrigerator that achieves both energy saving and temperature rise suppression in the freezer compartment according to the amount of frost formation can be realized.

  In addition, by having a defrosting means according to the amount of frosting during defrosting, by interlocking with a means for detecting by the door sensor that the door of the freezer has been opened and closed and the thermal load has entered the warehouse, A refrigerator having a means for ending the defrosting operation early can be realized.

  As described above, in this embodiment, the defrosting start temperature provided in the cooler at the start of the defrosting operation (measured by the temperature sensor provided in the cooler) and the temperature after a predetermined time (for example, provided in the cooler). The temperature gradient formed by the temperature detection sensor is approximately 0 ° C.) is compared with the temperature gradient determined in advance for determining the amount of frost formation, thereby determining the amount of frost formation. When defrosting operation using only the internal fan is started, when the above-mentioned means determines that the amount of frost formation is large, or when the thermal load increases due to opening / closing of the freezer compartment door, defrosting is performed during the defrosting operation. By turning on the heater, heat transfer between the frost and the surrounding air is promoted, and a means for changing to a method of shortening the defrosting time is provided.

  That is, as described in the above embodiment, the present invention adds the cold air generated when the internal fan or the internal fan and the defrost heater are used to defrost and defrost simultaneously at the time of defrosting operation. It is a system which cools the inside of a refrigerator by sending air to a refrigerated room or a vegetable room that becomes a temperature zone. By operating the internal fan, the air passing in the vicinity of the frost layer becomes forced convection, so heat transfer is accelerated and the defrosting time is shortened, and the generated cold air is blown to the refrigeration temperature zone and cooled. You can also

  In addition to being able to cool the chilled room and vegetable room with frost grown on the cooler, it has defrosting means to defrost the frost while performing cooling operation using the frost's cold energy during defrosting. Thus, it is possible to provide a refrigerator including a control unit that can achieve both energy saving and suppression of temperature rise in the freezer.

DESCRIPTION OF SYMBOLS 1 Compressor 4 Cooler 5 Fan in refrigerator 6 Refrigerating room damper 7 Refrigerating room cold air path 8 Refrigerator 9 Refrigerating room 9a, 9b Refrigerating room door 10 Upper freezing room 10a Ice making room door 10b Upper freezing room door 11 Lower freezing room 11a Lower Freezer compartment door 12 Vegetable compartment door 12 Vegetable compartment door 13 Freezer compartment damper 14 Freezer compartment cool air return port 17 Vegetable room return air channel 18 Defrost heater 19 Outer tray 20 Drain pipe 21 Vegetable room cool air return port 22 Discharge port 23 Partition wall 24 Duct 25 Inner tray 26 Defrost sensor 27 Signal line 30 Ice making chamber 31 Heat insulation box 32, 33 Heat insulation partition wall

Claims (3)

A refrigerated temperature zone and a freezing temperature zone provided in the refrigerator body;
A compressor provided in the refrigerator body for compressing refrigerant;
A cooler chamber provided behind the freezing temperature zone chamber and in which a cooler is disposed;
A blower for supplying cold air from the cooler chamber to the refrigeration temperature zone chamber and the refrigeration temperature zone chamber;
A refrigerating room damper for controlling the amount of cold air supplied to the refrigerating temperature zone chamber;
A freezer damper that controls the amount of cold air supplied to the freezing temperature zone; and
A defrost heater provided in the cooler chamber for defrosting the cooler;
Stop the compressor, open the refrigerator compartment damper, and close the freezer compartment damper to operate the blower to supply cold air to the refrigerator temperature zone chamber,
When the temperature gradient of the cooler is compared with a set value and it is determined that there is little frost formation, after the cooler reaches a predetermined temperature, the blower is stopped and the cold room damper is closed to operate the defrost heater And
When the temperature gradient of the cooler is compared with a set value and it is determined that there is a lot of frost formation, the defrost heater is operated to stop the blower after the cooler reaches a predetermined temperature and the refrigerator compartment damper A refrigerator characterized by closing.   2. The refrigerator according to claim 1, wherein at least one of an energization rate of the defrost heater and a rotation speed of the blower is controlled according to a frost formation amount of the cooler.   In Claim 1, it has a door sensor which detects opening and closing of the door of the freezing temperature zone room, and controls at least one of the energization rate of the defrost heater or the number of rotations of the blower according to the detection value of the door sensor. A refrigerator characterized by that.

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